feat: improve email mode messaging

[karrui]

Problem

This PR finally closes the first issue created in this repo.

Closes #1

Solution

Features:
Settings page

• when only 1 recipient email is entered, display "Recommended: at least 2 recipients to prevent response loss from bounced emails" info box.
• update 'Read about email reliability' link to Guarding against bounces' with new valid link
• change the toaster under 'authentication' to say 'Deactivate your form to change authentication method'

Create form modal

• amend copy of email mode slightly to "...Not recommended usually, especially for high volume forms...

Activation Email mode only

• New toaster messaging for email mode form activation that lasts for 10 seconds with link to autoarchive help.
• update deactivation toast messaging

Before & After Screenshots

BEFORE

Create form (Display text on only 1 email, new link and text, new discouragement copy)

Settings page (Display text on only 1 email, new link and text)

Settings page (new deactivation messaging)

Activation and deactivation text
Both have same text

AFTER

Create form (Display text on only 1 email, new link and text, new discouragement copy)

Settings page (Display text on only 1 email, new link and text)

Settings page (new deactivation messaging)

Activation and deactivation text

[mantariksh]

instead of adding a custom $watch, might it be better to add this logic in checkForErrors or vm.validateEmails? Then at least all the code which runs on changes to the emails input is all in one place

[karrui]

i want the initial load to also show the info message. Since vm.validateEmails only run on change, it is not suitable. I also tried just assigning to vm.emailInfoMsg directly, but vm.formData.emails may be undefined at the start and won't get updated when formData.email finally gets populated.